BRUSSELS — Uber Technologies Inc. drivers came under attack from taxi drivers in the Belgian capital over the weekend, in a burst of violence highlighting tensions in Europe over the growth of the California car-hailing company.

In at least 20 incidents, taxi drivers blocked Uber cars as they attempted to pick up passengers, threw eggs and in some cases dragged passengers into the street, Filip Nuytemans, Uber’s general manager in Belgium, said Monday.

The violence, which follows similar incidents in Amsterdam last week, was “probably the most intense” series of attacks encountered by Uber drivers anywhere in a single evening, said Ben Novak, a spokesman for the company.

Uber, a startup with a $41 billion valuation, has triggered a broad backlash in Europe by upending heavily regulated taxi marketplaces.

All the incidents were instigated by a “small group of taxi drivers” who “bullied and intimated” drivers for the company’s popular Uberpop service, Nuytemans said. The attacks ranged “from throwing eggs to taking keys, stealing phones to violence toward passengers, who were dragged out of the car by taxi drivers.”